Known releasing devices for this type of fuze generally comprise mechanical and/or pneumatic delay elements which effect ignition of the explosive charge of the mine only when the pressure applied to an ignition mechanism exceeds a certain magnitude and duration. This has the aim of preventing ignition of the explosive charge of the mine due to short-term, high pressure applied to the fuze mechanism, for instance due to shock waves resulting from shell detonating in the vicinity or from a roll-over device for mine clearance. Known releasing devices likewise do not respond to slight, long-lasting loads occurring, for example, on manual mine clearance.
In order to achieve a defined response sensitivity with known releasing devices, sophisticated precision designs are generally required which, furthermore, permit, only at additional expense of adjustable response sensitivity, to satisfy combat field conditions. Bearings for moving parts cannot be greased, for instance, since lubricants oxidize when mines are stored for a longer period of time, hence impairing the functioning of the releasing device. For this reason, all moving parts must be pivoted dry. This implies, however, precision manufacture and a considerable loss of accuracy.
On account of the sophisticated and, in addition, expensive precision design of the releasing device, the device is extremely sensitive to shocks occurring on a field of combat and hence no longer guarantees reliable application.